Another great tool from Park Tool Company...
Let's say you're installing a new headset. You've got to get the old headset off, which means getting the old crown race off. That is explained in our description of the J.A. Stein crown race remover.
Now you've got to put the new one on. It's a no brainer. You've got to press it on, like you press in the headset cups. But to term this operation "press" might be a tad antiseptic. You bang the thing on.
You want to make sure that you don't mess up your crown race surface in the process. Enter Park Tool's system, which has the -- well, the banger-oner, the hammer, the whatever you call it -- and a bunch of different fittings, one of which will fit over or onto your crown race nicely.
I've got to be honest with you, I look at all these fittings and I can't tell you which is which. Obviously some are for 1" headsets, others for inch-and-an-eighth, and so on. When I have to install a crown race I just try different fittings until I find one that isn't going to mess up the bearing surface.